Gideon West is a man tormented by his past. In an effort to block out his horrific memories, he focuses on the one thing that gives his new life meaning: his job as a vampire hunter for the Catholic Church. Torn between his faith and his desire for vengeance, Gideon is a man on the edge. Soon, as a new force in the vampire world rises to power, Gideon is going to be tormented far more than he ever dreamed possible. Unwillingly by his side is Sebastian, a wild, carefree vampire assigned as the stern hunter's guide. As the two unlikely allies uncover the truth, they quickly find that they go from being the hunters... to being the hunted.

Both Gideon West and Sebastian were inspired by the antics of Karlton Hargrove, even though he was oblivious of it. For one Halloween, Karlton dressed as a hardcore mercenary priest, complete with a bulletproof vest with a spray painted cross on the back. Mathew Shockley liked the contradictions in the concept, and started sketching designs for a character that he would name Gideon. He then created a second character named Sebastian, a loud-mouthed party animal vampire that (coincidentally, of course) resembled Karlton in appearance and personality. Mathew pitched his skeleton of a story concept to Karlton, and the two started brainstorming. After long hours of contemplation and many cups of coffee, the comrades settled on a storyline.

Gideon West walks a thin line. His life is a living hell: burdened by the guilt and torment of losing his family to a vampire long ago, he's escaped into a bottle. His only justification for his continued existence is his faith, which is a source of inner turmoil, and his job as one of the original vampire hunters sanctioned by the Catholic Church. He is, to coin a phrase, the best at what he does. When the church's power is threatened by a sudden and inexplicable uprising of a stronger vampire population, Gideon's leaders decide to take drastic proactive measures. They choose their best man, Gideon, to initiate a new phase in the vampire hunter program. They partner him with Sebastian, relying upon a vampire's "sixth sense" to detect others of their own kind, and effectively enabling the hunters to pinpoint and eliminate vampire targets.

The entire story of Gideon & Sebastian relies upon coincidence. Everyone in the story is connected in some way, even though all evidence may point to the contrary. As the web of mystery and conspiracy unravels around Gideon, he'll be forced to confront the greatest torment he's ever known: the truth.